Let's Make Robots!

Controlling 2 lcds

How would i control 2 16x2 lcds using a arduino mega? I know how to control 1 but i do not understand how to control 2 of them. Edit: i want to control them separately and i would hope i could just use the normal, non serial ones. That is i want to be able to use the liquid crystal library but that from what i can tell only controls one because when you lcd.print you are not saying to which one to print. I understand arduino mega has multiple serial lines so i guess maybe that would make it possible to use multiple serial lcds but i am not sure.

Why the need for pulldown resistors in some cases and not others? TeleFox?[solved I guess... mystery remains though]

Hi all,

This may be stupid but I need to understand.

The problem:

We have two microcontrollers:

1 Arduino based on ATMega168

1 ATTiny2313. 

Link three pins of your choice between them, for example

Arduino                     Tiny

9                 -            PB5

10                            PB7

11                            PD3

We want the tiny to respond to low/high states on the Arduino pins.

Computer Controlled RC Car with Wireless Camera


I wanna a project for my studies...

here is what i would like to make..

1. A RC Car that is controlled via computer and not by the its remote. i wanna create a application that controls the car and also displays real time video.

2. I wanna use zigbee (XBEE pro) for transmitting and receving commands and controls.

3. Wanna use mobile phone (wifi) camera for video transmission.


now i wanna know How can make this ???

1. which microcontroller should i use ????

2. which software should i use to make the compuetr app.

picaxe programming

Does the picaxe programming circuit need to be in place while a picaxe is running? In other words, can I use a breadboard and picaxe breadboard adapter ( http://www.sparkfun.com/commerce/product_info.php?products_id=8331 ) to program it and then put the chip on a pcb separate from the breadboard?

Motor drivers

Hi, i am searching after some motor drivers, l293, l298 to start with, if you got other motor drivers that can handle 2 motors and over 1amp, i might also be interesed in those.

I am living in Denmark

Schematic Drawing Program

Hey all

 I was wondering if anyone could suggest a good, free program I could use to draw up schematics on my computer. 

 Any suggestions would be appreciated.


5v voltage regulator

I'm using 5v regulator (this one:http://solarbotics.com/products/lm2937/) and it doesn't seem to be working correctly. I'm under the impression that this is how it should work:

Connecting sensors to a computer


iam making a line following robot without using a microcontroller. i was wondering how would i connect my ldr sensors to a computer so data can be analysed. i done some research and i found out that i need an a/d convertor, but iam not sure how to connect it up. :/

my general idea is to get data from sensors that will be send it  to a computer from sensors then the computer will tell the motor whether to turn left or right by stopping either the left motor or the right motor. iam not sure how the computer will send the data to motor wheels any suggestions?

Listen to LMR!

I came across a website called www.codeorgan.com that turns the code of any website into music! put the url for the LMR homepage in, and it sounds pretty good. I wouldn't expect less from LMR.

i have some questions!!!!

hello all........

i have some questions...... help me.


is it important to connect the remaining 3 analogue to V. because i cant understand that part in fRITSL start here robot.

if i want to put LEDs... can someone tell me with some drawings how to connect three LEDs in ur PICAXE,

is this the basic change in code

red LED for left turn( connect this to output 1)

Yellow LED for right turn(connect this to output 2)



high 1:high 6: low 5: low 7: high 4(left turn)